Function handle_channel_update

gossipd/routing.c:1539–1639

}

u8 *handle_channel_update(struct routing_state *rstate, const u8 *update TAKES,
			  struct peer *peer,
			  struct short_channel_id *unknown_scid,
			  bool force)
{
	u8 *serialized;
	const struct node_id *owner;
	secp256k1_ecdsa_signature signature;
	struct short_channel_id short_channel_id;
	u32 timestamp;
	u8 message_flags, channel_flags;
	u16 expiry;
	struct amount_msat htlc_minimum, htlc_maximum;
	u32 fee_base_msat;
	u32 fee_proportional_millionths;
	struct bitcoin_blkid chain_hash;
	u8 direction;
	struct pending_cannouncement *pending;
	u8 *warn;

	serialized = tal_dup_talarr(tmpctx, u8, update);
	if (!fromwire_channel_update(serialized, &signature,
				     &chain_hash, &short_channel_id,
				     &timestamp, &message_flags,
				     &channel_flags, &expiry,
				     &htlc_minimum, &fee_base_msat,
				     &fee_proportional_millionths,
				     &htlc_maximum)) {
		warn = towire_warningfmt(rstate, NULL,
					 "Malformed channel_update %s",
					 tal_hex(tmpctx, serialized));
		return warn;
	}
	direction = channel_flags & 0x1;

	/* BOLT #7:
	 *
	 * The receiving node:
	 *...
	 *  - if the specified `chain_hash` value is unknown (meaning it isn't
	 *    active on the specified chain):
	 *    - MUST ignore the channel update.
	 */
	if (!bitcoin_blkid_eq(&chain_hash, &chainparams->genesis_blockhash)) {
		status_peer_debug(peer ? &peer->id : NULL,
				  "Received channel_update for unknown chain %s",
				  type_to_string(tmpctx, struct bitcoin_blkid,
						 &chain_hash));
		return NULL;
	}

	/* If we dropped the matching announcement for this channel due to the
	 * txout query failing, don't report failure, it's just too noisy on
	 * mainnet */
	if (in_txout_failures(rstate, &short_channel_id))
		return NULL;

	/* If we have an unvalidated channel, just queue on that */